Furnace



H. A. POPPEN HUSEN.

FURNACE.

APPLICATION FILED JAN. 8, 1917.

Patented Mar. 30,1920.

|||h I 1 I l I l I l I l I Illlb I l 1 1 I I I I I l l I! l m mmwxm mm H. A. POPPENHUSEN.

FURNACE.

APPLICATION FILED JAN. 8, 1917.

2 SHEETS-SHEET 2.

Patented Ma r. 30,1920.

UNITED PATENT -ICE,

HERMAN A. POPPENHUSEN, OF. HAMMOND, INDIANA, ASSIGNOR TO GREEN ENGINEER.- ING'r COMEANY, OF EAST CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

FURNACE;

Specification of Letters Patent.

Patented Mar. 30, 1920.

Application filed January 8,.1917. SeriaLNo. 141,301;

State of Indiana, have invented new and useful Improvements in Furnaces, of which the following is. a specification,

This invention relatestoimprovements in furnaces of steam boilers, and more particularly to devices used in such furnaces for-the purpose of providing water cooled surfaces surrounding the fuel bed, whereby the walls and ash discharge passages may be kept free from formations of clinkers.

The invention is particularly applicable to furnaces employing the automatic or travel sirable that the fuel may be advanced freely through the combustion chamber, without accumulation of ash andclinkersupon the stationary portion of the furnaceadjacent to the grate.

The object of this invention is to provide a system of circulating tubes, preferably. utilizing the waterof the boiler as means for providing the cooling areas, for accomplishing-the desired results, and, further, to construct and arrange the tubes in such a manner that they can be readily cleaned, inthe same manner as, are the boiler tubesthemselves, it being manifest thatthepractica- V bility of a device'of thischaracter'depends upon'the possibility of frequent attendingto and cleaningof the tubes in order-,that

depositsof foreign matter 'in'the tubes .may be avoided, thus assurlng free circulation of the water, which is highly important owing;

to the great heat to which the-tubes are subj ected. The construction whereby the desired results are accomplished will be understood from the description whichv follows and in connection with the accompanying drawings, wherein Figure 1 is a view in vertical section of the furnaceof a steam boiler, showing the device embodying the features of the invention 111g grate type of stoker, wherein it is'de is especially suitable comprises the ordinary brick construction or setting of side walls 10, 10 and afront wall 12, inclosing the combustion chamber below the boiler tubes 13, which extend substantially horizontally from. front to rear of the furnace and, as is,

the risualpractice, are joined at their front ends to a header, or headers 14, supported in substantially vertical position adjacent the front wall and upon, the coking breast 15 extending. rearwardly over the combustion chamber. The rear ends of the tubes 13 are likewise connected to a rear header or headers (not shown) at the rear part of the furnace. at its rear end by a bridge wall 16, eXtendingupwardly from the foundation ofthe furnace tothe boiler tubes 13, said bridge wall being preferably provided with a forward extension or ledge 17, which projects over the rear end ofthe grate l8 and the discharge-passage to the ash pit below. The grate 18 is preferably of the travelingchain type,- consisting of an endless chain sup? ported upon a frame structure provided with rollers 19, which engage and support the chain intermediate its ends, and sprocket wheels 20 at, the front and rear ends. Suitable actuating mechanism for moving the grate is connected with a shaft 21, supporting, the forward sprocket wheels 20, whereby thefuelis advanced rearwardly through the combustion chamber upon the upper chain or surface of the grate, the fuel being fed onto'the grate from a hopper 22 at the forward end of the furnace.

Extending transversely of the combustion chamber, at the rear end of the grate and immediately below the projecting ledge 17 of the bridge wall 16, are two horizontal tubes 23 and 2 1, spaced apart vertically and arranged in parallel relation within the space or passage between the rear end of the grate 18 and said ledge 17 of-the bridge wall. This passage forms the opening through which the ashes are discharged from the grate into the ash pit below, the lower tube being spaced above the surface of the grate a distance suflicient to provide the desired size of opening. I The ends of the tubes 23 and 24: are supported in and com- The combustion chamber is closed.

preferably made in the form of hollow cast metal members, cubical in shape and elongated throughout their vertical dimensions. The junction boxes 25 and 26 are supported one upon the other, the lower pair of boxes 26 resting upon longitudinally extending ledge plates 27, 27, having the form of T-irons, mounted in the side walls in such a manner that they extend inwardly with the transverse web in vertical position and extending along and in close proximity to the side margins-of the grate. The ledge plates are, in turn, supported upon vertically arranged bloeks 28, 28, spaced apart at suitable intervals along the ledge plates and resting upon side frame members 29, 29 of the grate supporting structure, said members having inwardly extending flanges 30, 30 along their upper margins, upon which rest the blocks 28, 28.

Extending laterally from the outer sides of the junction boxes 25 and 26 and in axial alinement with the tubes 23 and 24, are short tubes 31, 31 and 32, 32, which are embedded in and extend through the side walls 10, 10, terminating just beyond the outer surface thereof. These tubes, though connected to the junction boxes independently of the tubes 23 and 24, are in reality extensions of said tubes, which serve in the following capacities: fThe tube extensions 31, 31 are provided at their ends with T-fittings 33, the outer ends being closed by removable plates and these lateral connections joined to pipes as follows: Connected to the lower pipe 26,- in the manner described, is the water supply or inlet pipe 34 (Fig. 1), extending rearwardly of the furnace, where it is designed to be connected to the rear header of the boiler, (not herein shown) preferably by inserting it in a tube opening thereof in the manner of a boiler tube. The upper tube 28, in like manner, communicates with a pipe 35 constituting the discharge line, extending upwardly and forwardly and connected to the front header 14 of the boiler, as shown in Fig. 1, or by utilizing a tube opening, as before described. The tube extensions 32, at the op posite or right-hand ends (Fig. 3) of the tubes 23 and 24, extend through the adjacent side wall 10 and are provided at their ends with fittings provided with removable caps or plates 36, adapted to normally close the ends of the tubes but capable of removal in order that cleaning tools may be inserted and the entire length ofthe tubes 23 and 24 cleaned, in the same manner and with the same type of tools as are the tubes of the water tube boilers ordinarily cleaned.

The junction boxes are provided with an open side, preferably the rear side, in order that access'may be had to the interior thereof for the purpose of cleaning, although especially for inserting and connecting the tubes to the boxes, this being ordinarily accomplished by tools which roll or upset the ends of the tubes from within the box, in much the same manner as boiler tubes are connected or set in the headers.

The openings, or hand holes as these are called, are normally closed by plates or covers 37, held in position by the usual arrangement of yokes 38 and tightening screws 39.. V V.

Extending forwardly from each pair of junction boxes 25 and 26, is a set of U-connected branch tubes, that is, a pair of parallel tubes 40 and 41 connected at their outer ends to form a U-shaped tube, each tube being designed to communicate at its open or rear end with one of the transverse tubes 23 or 24, through the medium of the junction boxes 25 and 26. These sets or pairs of tubes 40 and 41 extend at right angles to the transverse tubes, along the side walls of the combustion chamber and above the side margins of the grate, substantially throughout the length of the grate between the rear end thereof and the front wall 12 The branch tubes are likeprovided on both sides of the combustion chamber, are connected together at their outeror forward ends by means of junction boxes 42, 42, not unlike the boxes 25 and 26 heretofore described, the tubes being inserted in the rear walls thereof and con- I nected in the usual manner. The junction boxes 42 are preferably set or embedded in the front wall 12 of the furnace, the rear walls being preferably flush with the inner Immediately forsurface of the front wall. ward of the boxes, a portion of the front wall is removed, thereby forming a cavity 43 opening outwardly toward the front of the furnace and exposing the front wall of the box, said front wall being provided with an opening or hand hole, which is normally closed by a cover plate 44, held in place by a yoke 45 and a screw 46 of the usual construction. By this means, therefore, the branch tubes may be cleaned by opening the hand holes and inserting the cleaning tools, the operation being accomplished entirely from-the exterior of the furnace and from the front'thereof. 7 With the arrangement of tubes and junction boxes constructed as described, the water enters the lower left-hand junction box 26 (Fig. 8) through the supply pipe 84: and lower tube extension 31, and from said junction box the water is conducted through the lower transverse tube 24 into the cor.- responding lower junction box 26 on the opposite side of the combustion chamber. From the lower junction boxes 26, 26, the outlet for the water is through the lower tubes 40, 40 of branch tubes, where it passes into the junction boxes 4C2, 2 at the front end of the furnace, and returns to the upper junction boxes 25, 25 through the upper tubes 41, 41, the water from the right-hand set of branch tubes being discharged through the upper transverse tube 23 into the upper left-hand junction box 25, the water being dischargedfromsaid box through the upper tube, extension 31 and discharge pipe 35 and returned to the boiler at the front header lat. In this manner thewater is taken from the boiler at its rear end, passed through the tubes in the combustion chamber, and again discharged into the boiler at its front end, thus the direction of flow of the water through the device corresponds to the general direction of water circulating through a boiler, that is, from the rear header forwardly through the boiler tubes into the frontheaders and return, thecirculation or flow being inducted or maintained in the tubes by reason of the difference injtemperature of the water entering and leaving the system.

As has been before suggested, the function of the described arrangement of tubes is to provide water cooled surfaces surrounding the fuel bed, to which the semi-molten ashes will not adhere, thereby eliminating the formation of clinkers. Thus the transverse tubes serve to keep the discharge opening for the ashes free from cl'inkers, whereas the side tubes serve in the same manner to prevent the formation of clinkers along the side walls of the furnace. Furthermore, the

7 tubes perform a reciprocal function, namely,

to increase the heating surface of the boiler, inasmuch as the tubes conduct the boiler water through the combustion chamber, where the temperature is raised to a considerable degree. The presence of the tubes, therefore, increases the capacity of the boiler, without increasing the size of the boiler or number of boiler tubes.

The advantages of a construction of the device as herein described are not limited to the results accomplished by its use, but of equal importance, as before suggested, is the accessibility of the parts for the purpose of cleaning and otherwise maintaining the same in perfect condition. The provision of openings at the ends of the tubes and in the junction boxes, located exterior of the furnace or accessible therefrom, permits frequent cleaning and inspection of the tubes, thereby insuring the device against stoppage of the circulation and premature burning out of the tubes and the dangerous con ditions that would result.

The construction embodyin the features of the invention is more speci cally set forth in the appended claims.

I claim as my invention:

1. In a furnace, the combination of a grate mounted in the combustion chamber of the furnace, pairs of junction boxes mounted on opposite sides of the combustion chamber? above the grate, transverse tubes connecting the corresponding junc tion boxes of each pair, a set of branch tubes communicating with each pair of junction boxes, tube extensions connected, with said junction boxes and extended through the sidewalls of the furnace, and a junction box connectingthe outer ends of said branch tubes.

2. In a furnace, the combination of a grate mounted in the combustion chamber of the furnace, pairs of junction boxes mounted on opposite sides of the combustion 011M115 ber above the grate, tube extensions connected with said junction boxes and extended through the side walls of the furnace, transverse tubes connecting the corresponding boxes of each pair, water supply and discharge tubes communicating with said tube extensions and transverse tubes, and a set of U-connected branch tubes communicating with each pair of junction boxes and eX- tending along the sides of the combustion chamber above the margins of the grate.

3. In a furnace, the combination of a grate mounted in the combustion chamber of the furnace, water supply and discharge tubes extending transversely of the combustion chamber and through the side wall of the furnace at one of their ends, a connection between the front header of the boiler and one of said tubes exteriorly of the furnace, and a set of U-connected branch tubes communicating with said transversely arranged tubes and extending along the sides of the combustion chamber above the margins of the grate.

a. In a furnace, the combination of a grate I110Ul1t-6Cl in the combustion chamber of the furnace, water circulating tubes extending transversely of the combustion chamber, above the rear end of the grate, and a pair of U-connected branch tubes arranged closer together than said first-named tubes and at a greater distance from the grate than the lowermost of said first-named tubes, said branch tubes communicating with said transverse tubes and extending forwardly along the sides of the combustion chamber, above the grate, and terminating adjacent the front wall of the furnace, the open ends of said branch tubes being accessible from the exterior of the furnace.

5. In a furnace, the combination of a grate mounted in the combustion chamber of the furnace, water circulating tubes extending transversely of the combustion chamber, above the rear end of the grate, pairs of junction boxes at the ends of said tubes, sets of branch tubes arranged closer together than said first-named tubes and at a greater distance from the grate than the lowermost of said first-named tubes, said branch tubes communicating ithsaid unction boxes and extending forwardly along the sides of the combustion chamber, and a junction box connecting the forward ends of said branch tubes, said'box being provided with a removable wall accessible from the exterior of the furnace.

6. In a furnace, the combination of a grate mounted in the combustion chamber of the furnace, water circulating tubes extending transversely of the combustion chamber, above the grate, the ends of said tubes extending through the side walls of the furnace, removable fittings closing the open ends of said tubes pairs of branch tubes arranged closer together than said first-named tubes and at a greater distance from the grate than the lowermost of said first-named tubes, said branch tubes communicating with said transverse tubes and extending along the sides of the combustion chamber,

and a junction box mounted in the end wall of the furnace and connecting the outer ends grate mounted in the combustion chamber of the furnace, water circulating tubes extending transversely of the combustion chamber, above the rear end of the grate, junction boxes at the ends of each of said tubes and supported adjacent the side walls of the combustion chamber, water inlet and discharge pipes communicating with one pair of said junction boxes, pairs of branch tubes arranged closer together than said firstnamed tubes and at a greater distance from the grate than the lowermost of said first= named tubes, said branch tubes communicating with said junction boxes and extending forwardly along the sides of the combustion chamber and above the grate, and a junction box connecting the front ends of said branch tubes and mounted in the front wall of the furnace, said box having a removable wall, accessible from the exterior of the furnace.

In testimony that I claim the foregoing as my invention I aflix my signature in the presence of two witnesses, this 14th day of December, A. D. 1916.

' HERMAN A. POPPENHUSEN.

Witnesses A. S. BRADY, W. R. Woon. 

